Name: Stian Klaassen
Born: Apr. 19, 2003
Sport: Tennis
School: University of San Diego
Placed: Fall 2021

About Stian
Stian Klaassen is a driven and technically strong tennis player with an impressive international trajectory. Originally from the Netherlands, where he was one of the top Dutch youth players for many years, he trained at Tjerk Bogstra’s academy. At the age of 16, he crowned himself National Under-16 champion, underscoring his status as a top talent.
At a young age, Stian moved with his family to Toronto, Canada, where he continued his tennis career at a high level. He trained intensively at Mayfair West and climbed to an ITF Juniors ranking of #383. His style of play is characterized by attacking tennis, a powerful forehand and a refined one-handed backhand. He also excels in variety and speed, and constantly strives to improve in his service and net play.
The road to America
After completing his high school in Canada, Stian’s focus was on combining sports and studies at the highest level. He dreamed of a place at an ambitious university with a strong tennis program as well as academic challenge. He found that perfect match at the University of San Diego, where he became part of an NCAA Division 1 top team.
The road there, however, was not without obstacles. Due to an injury, he had temporarily played fewer games leading up to his transfer. That caused his level to appear lower on paper than in reality. As a result, he started with a lower scholarship. But Stian wouldn’t be Stian if he put up with that – with his perseverance and performance on the court, he soon managed to prove his worth. In no time, he secured a permanent spot in the team’s lineup and earned a full scholarship.

Sporting success
The switch to the American system went surprisingly smoothly. Stian immediately felt at home in the team and grew to become a regular force within the selection. His commitment, game intelligence and winner’s mentality did not go unnoticed: University of San Diego achieved an all-time high ranking of #6 in the NCAA Division 1 in 2025 with Stian – a historic achievement for the program. And if that wasn’t enough, Stian also managed to win the National title with his doubles partner.
His development in college is impressive. Not only athletically, but also academically. Stian combines his tennis schedule with his interests in business, economics or accounting, building a solid future – both on and off the court.
Slamstox’s role
Slamstox played a supportive role in the process toward San Diego. With the right connections and good rapport with the university, Stian was helped to the place that exactly fit his ambitions.
What has stayed with me most of all is Stian’s resilience and dedication. Despite setbacks, he continued to believe in his path, gave his all and proved that perseverance is always rewarded in the end.
With an impressive start in American college tennis, a growing academic background and a strong personality on and off the court, the future lies open for Stian Klaassen. His ultimate goal? A professional tennis career – and following his path so far, that seems anything but a dream.
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